Duplex pump



Dec' 3, l1940- B. D. BARTQN Erm. 2,223,592

DUPLEX PUMP Filedoct. .3.l 1938 2 sheets-sheet 1 WATER TANK Z] AJ5 12 4 Z EL TNVENTORS en D50/"fon IZ e 'M A TORNEYS Dec. 3, 1940.

B. D. BARTON EI'AL DUPLEX PUMP Filed 001'.. 5, 1938 2 sheets-sheet 2 INVENToR Patented Dec. ,3, 1940y DUPLEX PUIVIP Ben D. Barton, Adrian P. Adney, and Harold A.

Bentley, Battle Creek, Mich., assignors to American-Marsh Pumps, Inc., Battle Creek, Mich., a corporation of Michigan Application October 3, 1938, Serial No. 232,992

8 Claims.

This invention relates to improvements in duplex pumps.

The main objects of this invention are:

First, to provide a duplex pump suitable for re apparatus and adapted to be operated selectively for single-stage or multi-stage operation.

Second, to provide a pump of the type described controlled and driven by a selective gear transmission well adapted to be connected with the drive for an automotive vehicle.

Third, to provide a duplex pumping system comprising a plurality of rotary centrifugal pump units or members having different pumping characteristics and means for selectively driving the same to function separately or in series.

Fourth, to provide a duplex pumping mecha-- nism having a plurality of rotary pumps driven from a common drive and transmission and arranged to operate with a common suction and discharge.

Fifth, to provide a multiple-stage pump having novel provisions whereby the -pumps thereof are adapted to be driven separately or in unison and whereby when either of the pumps is driven separately the other is automatically kept primed for instant operation when desired and to prevent freezing thereof.

Sixth, to provide a pumping mechanism of the type described and a novel arrangement for priming one of the pumps by means of the other.

Objects relating to details and economies of the invention will appear from the description to follow. The invention is dened in the claims.-

A preferred embodiment of the invention is illustrated in the accompanying drawings, in which: i.

Fig. 1 is a fragmentary plan view partially broken away and in section illustrating one embodiment of the invention.

Fig. 2 is a view in side elevation partially broken away and in section illustrating certain of the features of the invention.

Fig. 3 is a fragmentary front View partially broken away `and also in section on line 3-3' of Fig. 1, illustrating further details.

Fig. 4is an enlarged fragmentary, detail view l in sectio"6n`lirie 4-4 of Fig; 1..

Fig. 5 is an enlarged fragmentary'view partially broken away and in section on line 5-5 of Fig. 2.

I'he present invention relates to a pumping system or mechanism which is particularly adapted for use in automotive re fighting and general field or portable service pumping. The embodiment illustrated is designed to be driven from the drive of a motor vehicle. One feature of the invention relates to provisions whereby the the same may be selectively driven either independently of one another or together in staged or series relation, and automatic priming and freezing preventing provisions of great utility.

Referring to the drawings, the reference numeral I in Figs. 1, 2, and 3 generally indicates the pumping system or mechanism of the invention, which consists of a main suction header 2 adapted to be connectedby suitable means such as a hose (not shown) with a source oi' water, for example, a hydrant, tank, or reservoir, a river, ditch,

or the like. This main conduit leads through a branch 3 to the intake of a suitable large capacity rotary centrifugal pump of suitable type which is generally designated 4.

The pump 4 discharges into a` valve housing 5, see Figs. 1 and 3, through a check valve 1, the valve of this embodiment being a gravity closed poppet type valve. The pressure of the discharge from the pump 4 serves to unseat the valve 'I as will be understood. The valve housing 5 communicates through a passage 8 with the discharge line which is designated by the reference numeral ilv and which will be connected to a suitable discharge hose or conduit.

There is arranged coaxially with the pump 4 in a manner to be hereinafter described a second rotary centrifugal pump I0 which is of the high pressure type. -The intake chamber Il of this pump is connected through a pipe I2 and other suitable ttings with the main conduit 2, there being a check valve I3 inserted in the pipe I2 in the manner illustrated in Fig. 1, which will permit ow of uid in the intake direction indicated by the arrow, but will prevent iiow in the reverse direction.

The discharge I4 of the pump-I0 leads to a valve housing I5, Fig. 2, through a port I6 controlled by check valve I1. The valve I'I of this embodiment is of the gravity actuated poppet type similartolthe valve l. 'I'he valve chamber I5 communicates through a tting I8 with the discharge pressure of the pump IU in a manner i which will be apparent.

A by-pass is provided between the discharge of the pump 4 and the intake of the pump III forl use when the pumps are being run together in staged or series relation. This by-pass is designated by the reference numeral I9 and consists of a pipe 20 and other suitable fittings communicating with the discharge of the pump 4 below the valve 1, as illustrated in Fig. 3, and a further pipe 2I communicating with the intake chamber I I of the pump I0, as illustrated in Fig. 2. The

pipes 20 and 2| are connected together through a suitable check valve 22, a ap valve being shown in Fig. 1, the function of which will be referred to.

Pipe 2| communicates through a manually operable valve 23 with a Water tank 24 or other source of water to be used in priming, as will be hereinafter described, which in actual practice is arranged above pump Irto cause a flow of water thereto by gravity when the tank is used. Other priming provisions in the system include a circuit consisting of a pipe 25 connected at 26 to the discharge pipe 9, see Fig. 1. The pipe 25 is connected through a valve 21 and a suitable fitting or nipple 28 with an ejector chamber 29, as illustrated in Fig. 4, this chamber being communicated with the interior of the pump 4 and also with a water and air exhaust line 30 leading back to the tank 24. A manually controlled valve 3| is placed in this line. The operation of the above described ejector for priming pump 4 when the system is initially placed in operation will be apparent. When water is supplied under pressure from the line 9 and pump I8 through the pipe 25, the effect is to withdraw air from the pump 4 and thereby prime thc` same, the Withdrawn air and the ejector water being returned to the tank 24 I where they are separated.

The invention includes means whereby the pumps 4, I0 may be selectively driven separately depending upon the existent condition which must be met; i. e., either the high capacity or volume of pump 4 may be availed of or the smaller capacity but higher pressure of the pump I Il may be used. Alternately, pumps 4 and I0 may be driven together in staged or series relation with the output of pump 4 supplied to the intake II of the pump I0.

The aforesaid provisions whereby a proper drive for the selective operation of the pump' is made possible and the provisions whereby the system is selectively coupled with the drive shaft of the vehicle or other suitable drive shaft are clearly illustrated in Fig. 5. Referring to that gure, the reference numeral 32 designates a gear case interposed between the pumps 4 and I0, having bearing provisions therein for the respective shafts 34 and 33 of pumps 4 and I8. Gears 35, 36 of smaller and larger diameter, respectively, are fixed to the shafts 33, 34. The automobile propeller shaft or other driving shaft is illustrated in dotted lines and indicated by the reference numeral 31. 'This shaft, in the embodiment illustrated, is connected to the automobile transmission in a. well known manner and it extends into and has a suitable bearing 38 in a housing or case 39 secured to the gear case 32. The shaft 31 is splined for a considerable lengthwise distance within the case 39 for a purpose to be described.

The housing 39 on the side thereof opposite the shaft 31 has an extension 40 secured thereto which ls provided with bearings 4I for a rotary clutch member 42 connected to the axle drive ter may be adjusted to drive either pump indeshaft 43 illustrated in dotted lines. The clutch member 42 on its inner side has an annular flange 44 provided with internal teeth 45. These'teeth 45 are adapted to mesh with a gear or` pinion clutch member 46 integral with a gear 41 which 5 y is slidable on the splined end of the shaft 31. The outermost end of the last named shaft is rotatably mounted in a bearing 48 carried by the clutch member 42. The gear 41 has the hub thereof grooved annularly at 49 to receive a shifter fork 50 for sliding the gear axially on the shaft 31 so that the clutch gear member'46 is engaged with or disengaged from the teeth 45, as will be understood.

The gear 41 servesv as the primary drive member for the pumps 4, I8 from the shaft 31. It is selectively connected to the pumps through a cluster gear member generally designated 5I having a pair of integral gears 52, 53 of larger and smaller respective diameter adapted to mesh with 20 the pump drive gears 35, 36 respectively. The arrangement is such that high pressure pump I0 is driven at a higher sp'eed than high capacity pump 4 for a given engine speed. The gear cluspendently or to drive them simultaneously, depending upon the lateral position of the gear member 5I. The teeth of the gears 52, 53 are suiiiciently wide and strong to permit thisselective individual or combined engagement. The gear 52 is in mesh with the gear 41 when the pumps are to be driven.

The cluster gear member 5I is slidable axially` of a splined jack shaft 54 mounted in suitable bearings in case 32 and the hub of the gear member 5I is annularly grooved to receive a shifter fork 55 whereby the lateral position of the member 5I may be manually controlled.

From the foregoing, it will be seen that by manipulation of the shifter fork 50, .the transmission shaft 31 is 'drivingly connected to the axle when the clutch gear 46 is engaged with the teeth 45. At this time the gear 41 is out of mesh with the gear 52; however, when the parts are in the position illustrated in Fig. 5, the gear 41 is 45 drivingly engaged with the gear 52. In the position illustrated, the cluster gearmember 5I is arranged whereby the gear 36 and high capacity pump 4 are driven. To disconnect this pump and to drivingly connect the pump I I), it is necessary only to manipulate the shifter fork 55 to bring the gears 35, 52 in mesh, and a's noted above both pumps may be driven by manipulating the gear member 5I to cause the respective gears 36,

- 53, and 35, 52 to mesh simultaneously. It will be 55 understood that as cluster gear member 5I is shifted laterally as described the gear 41 is shifted. therewith to keep gears 41, 52 in mesh. This simultaneous movement may be effected by means of suitable provisions (not shown) for connecting 60 forks 58, 55 for movement in unison but permitting movement of gear41 out of mesh with gear 52 when it is desired to disconnect the pumps from shaft 31.'

Referring to Figs. 1, 2, and 3, when the pump 4 65 alone is driven, it discharges to pipe 9. At this time, the valves 23, 21, and 3| willbe closed. During the operation of pump 4, the pump I0 is always kept primed, ready for vinstant operation if desired, by the iiow of water from pump 4 70 through by-pass I9 and the ap valve therein to and through the casing of pump 4, thence to discharge 9. 'Ihis lls the casing of pump I8 and maintains a circulation therethrough, enabling the same to be brought into instantaneous action i 2,223,592 i merely by shifting gear 52 into mesh with gear 35.

The flow of water also prevents freezing of the pump in cold weather.

When the pump I0 alone is driven, it discharges to pipe 9, the discharge valve 1 of the pump 4 being then closed by the pressure of pump I0 and the valves 23, 21, and 3| being closed. At this time, the vacuum at the intake II is effective through by-pass I9 to induce a flow of water through the by-pass, hence through the casing of pump 4, from main header 2. This keeps pump 4 in primed condition and prevents possibility of its freezing. It will thus be seen that our invention provides a duplex pumping system wherein the pumps thereof automatically prime one another, once either thereof is placed in operation, without vthe manipulation of valves or other attention. A further result is that when pump I0 is running alone the intake chamber II is supplied from two sources, i. e., pipes I2 and 2|, to insure delivery of an adequate volume thereto.

When it is desired to drive the pumps 4, I0 simultaneously in staged or series relation, the valves 23, 21, and 3| are closed. In such case, the pump 4 discharges through the by-pass I9, consisting of the pipes 20 and 2| and valve 22, into the intake chamber of the pump `|0. Pump I0 then impels the water past its valve I1 through fitting I8 to the discharge pipe 9. At this time, the pressure exerted below the same by the discharge from the pump 4 and accordingly the valve will remain closed. Furthermore, sulilcient pressure will be built up in the pipe I2 to maintain the valve I3 closed, whereby the pump I0 will be supplied only from the pump 4.

By means of the structure described above, it is possible to prime the pump 4 by the jetting principle. In this case, the ejector valve 21 and the valve 3| in thereturn or exhaust line 30 are opened; likewise, the valve 23 is opened. The pump/I0 thereupon takes water from the tank 24, forces the same to the pipe 9, thence through the pipe 25 and the ejector 29 to extract air from the pump 4. Valve 22 prevents reverse flow in by-pass I9 at this time. The water and extracted air are then returned to the tank 24 for separation. These priming instrumentalities are availed of only in initially priming pump 4 when commencing operations. Thereafter pumps 4 and Ill are self-priming, as described above.

It is to be understood that the term rotary is employed in the foregoing specification and in certain volf the claims to follow in its broad sense, i. e., as distinguishing from the reciprocating type and not necessarily to designate a positive displacement rotating pump as contrasted to a centrifugal pump, but, on the contrary, to include both of the last named types.

The Kaforesaid system is exceedingly compact and eiiicient; it is convenient to mount on any automotive or other driving device; and it affords a considerable range of operating capacities or pressures without increasing the bulk of the system. Moreover, it primes itself automatically, rendering it instantly capable of any desired type of pumping or of changes from one type to'another. These advantages are due to the use of a common drive for the two pumps,like wise a common .suction and discharge, and further to the means for selectively bringing the pumps into operation whereby the pump having the correct desired operating characteristic is available.

We have illustrated and described our improvements in an embodiment which we have found very practical. We have not attempted to illustrate or describe other embodiments or adaptations as it is believed this disclosure will enable those skilled in the art to embody or adapt our improvements as may be desired.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A duplex pump adapted to be mounted on an automotive vehicle and driven thereby, comprising a pair of rotary pumps of different characteristics adapted to be driven individually 'and independently of one another or as a unit, common supply and discharge means for said pumps, means for staging the pumps when they are driven as a unit comprising a by-pass connected to the output of one of said pumps and to the intake of the other thereof, the first-stage pump having a discharge valve to said common discharge subject to the difference in fluid pressure produced by said rstand second-stage pumps when the pumps are operated as a unit, a source of priming liquid, and means connected to said source and by-pass for initially priming said one of said pumps by the other and including hydraulic air evacuating means connected to said one of said pumps and actuated by the output of the other, said by-pass including means for preventing reverse iiow therein to said one of the pumps during said initial priming.

2. A duplex pump comprising a pair of rotary pumps of diierent characteristics adapted to be driven individually or as a unit, common supply and discharge means for said pumps, and means for staging theA pumps when they are driven as a unit and for maintaining the non-operating pump primed when one of the pumps is driven individually, comprising a by-pass connected to the output of one of said pumps in advance of the common discharge and to the intake of the other thereof, a pressure responsive valve in the by-pass yieldable to permit flow therethrough during staged operation, and priming means including avsource of priming liquid connected to said by-pass between said intake and said valve. and a hydraulic air evacuating device connected to the output of said other pump and to the 50 put oi.' said lower pressure pump in advance of 6 said valve and to the intake of the other pump, whereby during staged operation said valve is maintained closed due to the difference in pressure of the liquid in said common discharge maintained by the higher pressure pump and the discharge pressure of the lower pressure pump, and means for priming said first named pump including a source of'priming liquid connected to said by-pass between the intake ofthe higher pressure pump and the casing of the lower pressure pump, said by-pass having a pressure responsive valve therein for preventing reverse .fiow of the liquid in the by-pass during priming.

4'. A duplex pump comprising a high capacity rotary pump, a high pressure rotary pump, common supply and discharge means for said pumps connected to the respective intakes and outlets thereof, said pumps being adapted to be driven individually or together whereby to eilect staged operation thereof, means for connecting the discharge of said rst named pump with the intake of said second named pump for staged operation, comprising a by-pass having a check valve therein, and means for initially priming said rst named pump by means of said second named pump, comprising means for connecting said by pass between said intake and check valve to a source' of fluid supply, and a hydraulically actuated air evacuating device connected to the casing of the first named pump and to said common discharge, said check valve closing during said initial priming but opening during individual operation of said pumps whereby to permit the same to prime one another.

5. A duplex pump comprising a first rotary pump, a second rotary pump, means for supplying uid to the intakes of said pumps, said pumps being adapted to-be driven individually or together whereby to eiect staged operation thereof, a by-pass having a check valve therein for connecting the discharge of said first named pump with the intake of said second named pump for staged operation, and means for initially priming said rst pump by means of said second pump, comprising means for connecting the by-pass of said second pump to a source of fluid supply at a point between the valve and intake of said second pump, an ejector connected to said rst pump whereby to extract air therefrom when the ejector is operated, and means for connecting the ejector with the discharge of said second pump to operate the same, said valve preventing reverse ilow in the by-pass during priming, said by-pass permitting a flow of fluid through either one of said pumps .when the other Iis being operated individually to prime the non-operating pump' t I 6. A duplex. pump comprising a rst pump, a second pump, means for connecting said pumps in series, and means for initially priming said iirst pump by means of said second pump, comprising means for connecting said rst named means to a source of uid supply, means to prevent reverse flow to said first pump during initial priming, an ejector connected to said rst pump whereby to extract air therefrom when the ejector is operated, and means for connecting the ejector with the discharge of said second pump.

7. A pumping system comprising a rotarypump having relatively high capacity and low pressure in operation, a. second rotary pump having relatively high pressure and low capacity in operation, said pumps being adapted to be driven individually and independently of one another or together as a unit whereby to effect staged operation thereof, common discharge means connected to the discharge of each of said pumps, and means for connecting said pumps for staged operation, comprising a by-pass continuously open while the system is pumping leading from the discharge of the rst named pump to the intake of the second named pump and at all times permitting ow of liquid in the direction from said discharge to said intake, and a pressurev actuated valve controlling the discharge of said first named pump to said common discharge, said by-pass being connected to the discharge of the first named pump on the side' of the valve op posite said common discharge whereby during staged operation said valve is maintained closed by a difference in the forces exerted on opposite sides thereof arising from the different pressure characteristics of the pumps. l

8. A pumping system comprising a pump having relatively low pressure in operation, a second pump having relatively high pressure in operation, said pumps being adapted to be driven individually and independently of one another or together as a unit whereby to effect staged operation thereof, common discharge means connected to the discharge of each of said pumps, and means for connecting said .pumps for staged operation, comprising a by-pass continuously open while the system is pumping lead'mg from the discharge of the first named pump to the intake of the second named pump and at all tines permitting ow of liquid in the direction from said discharge to 'said intake, and a pressure actuated valve controlling the discharge of said rst named pump to said common discharge, said by-pass being connected to the discharge of the first named pump on the side of the valve opposite said common discharge whereby during staged operation said valve is maintained closed by a difference in the forces exerted on opposite sides thereof arising from the different pressure characteristics of the pumps.

BEN D. BARTON. ADRIAN P. ADNEY. -HAROLD A. BENTLEY. 

